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1.
Eur Rev Med Pharmacol Sci ; 28(8): 3275-3286, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38708486

RESUMO

OBJECTIVE: This study aimed to compare two routes of administration and different dosages of streptozotocin (STZ) for the pharmacological induction of gestational diabetes mellitus (GDM) in pregnant CD1 females. MATERIALS AND METHODS: 35 female CD1 mice were divided into 5 groups (n = 7). Diabetes mellitus (DM) was induced with STZ by two routes and two doses: 1) Control Group without administration of STZ (CL), 2) Intraperitoneal Group with 200 mg of STZ/Kg of weight (IP200), 3) Intraperitoneal Group with 230 mg of STZ/Kg of weight (IP230), 4) Subcutaneous Group with 200 mg of STZ/Kg of weight (SC200) and 5) Subcutaneous Group with 230 mg of STZ/Kg of weight (SC230). Body weight, food and water intake, glycemia, Homeostatic Model Assessment of Insulin Resistance Index (HOMA-IR), survival, and birth rate were identified. RESULTS: The SC230 group turned out to be the most effective dose and route for the induction of GDM in pregnant females. This scheme managed to reproduce sustained hyperglycemia with high HOMA-IR, the presence of polyphagia, polydipsia, and weight loss. In addition, the birth rate and survival were high compared to the other doses and routes of administration. CONCLUSIONS: The administration of a single dose of 230 mg/kg of weight by subcutaneous route supposes advantages compared to previously used models since it decreases the physiological stress due to manipulation and the costs since it does not require repeated doses or adjuvants such as high lipid diets to potentiate the diabetogenic effect of STZ. Graphical Abstract: https://www.europeanreview.org/wp/wp-content/uploads/Graphical-abstract-12.jpg.


Assuntos
Diabetes Mellitus Experimental , Diabetes Gestacional , Estreptozocina , Animais , Feminino , Gravidez , Camundongos , Diabetes Mellitus Experimental/induzido quimicamente , Estreptozocina/administração & dosagem , Injeções Subcutâneas , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Resistência à Insulina , Peso Corporal/efeitos dos fármacos
4.
Sci Total Environ ; 923: 171390, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38438044

RESUMO

Marine microdebris (MDs, <5 mm) and mesodebris (MesDs, 5-25 mm), consist of various components, including microplastics (MPs), antifouling or anticorrosive paint particles (APPs), and metallic particles (Mmps), among others. The accumulation of these anthropogenic particles in macroalgae could have significant implications within coastal ecosystems because of the role of macroalgae as primary producers and their subsequent transfer within the trophic chain. Therefore, the objectives of this study were to determine the abundance of MDs and MesDs pollution in different species of macroalgae (P. morrowii, C. rubrum, Ulva spp., and B. minima) and in surface waters from the Southwest Atlantic coast of Argentina to evaluate the ecological damage. MDs and MesDs were chemically characterized using µ-FTIR and SEM/EDX to identify, and assess their environmental impact based on their composition and degree of pollution by MPs, calculating the Polymer Hazard Index (PHI). The prevalence of MDs was higher in foliose species, followed by filamentous and tubular ones, ranging from 0 to 1.22 items/g w.w. for MPs and 0 to 0.85 items/g w.w. for APPs. It was found that macroalgae accumulate a higher proportion of high-density polymers like PAN and PES, as well as APPs based on alkyd, PMMA, and PE resins, whereas a predominance of CE was observed in surrounding waters. Potentially toxic elements, such as Cr, Cu, and Ti, were detected in APPs and MPs, along with the presence of epiplastic communities on the surface of APPs. According to PHI, the presence of high hazard score polymers, such as PAN and PA, increased the overall risk of MP pollution in macroalgae compared to surrounding waters. This study provided a baseline for MDs and MesDs abundance in macroalgae as well as understanding the environmental impact of this debris and their bioaccumulation in the primary link of the coastal trophic chain.


Assuntos
Alga Marinha , Poluentes Químicos da Água , Plásticos , Monitoramento Ambiental , Ecossistema , Argentina , Poluentes Químicos da Água/análise , Microplásticos
6.
Soil Use Manag ; 40(1): e12951, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516181

RESUMO

Riparian buffers are expedient interventions for water quality functions in agricultural landscapes. However, the choice of vegetation and management affects soil microbial communities, which in turn affect nutrient cycling and the production and emission of gases such as nitric oxide (NO), nitrous oxide (N2O), nitrogen gas (N2) and carbon dioxide (CO2). To investigate the potential fluxes of the above-mentioned gases, soil samples were collected from a cropland and downslope grass, willow and woodland riparian buffers from a replicated plot scale experimental facility. The soils were re-packed into cores and to investigate their potential to produce the aforementioned gases via potential denitrification, a potassium nitrate (KNO3 -) and glucose (labile carbon)-containing amendment, was added prior to incubation in a specialized laboratory DENItrification System (DENIS). The resulting NO, N2O, N2 and CO2 emissions were measured simultaneously, with the most NO (2.9 ± 0.31 mg NO m-2) and N2O (1413.4 ± 448.3 mg N2O m-2) generated by the grass riparian buffer and the most N2 (698.1 ± 270.3 mg N2 m-2) and CO2 (27,558.3 ± 128.9 mg CO2 m-2) produced by the willow riparian buffer. Thus, the results show that grass riparian buffer soils have a greater NO3 - removal capacity, evidenced by their large potential denitrification rates, while the willow riparian buffers may be an effective riparian buffer as its soils potentially promote complete denitrification to N2, especially in areas with similar conditions to the current study.

7.
Clin Transl Radiat Oncol ; 45: 100753, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38433951

RESUMO

Background: Pancreatic Stereotactic Body Radiotherapy (SBRT) allows for the administration of a higher biologically effective doses (BED), that would be essential to achieve durable tumor control. Escalating treatment doses need a very accurate tumor positioning and motion control during radiotherapy.The aim of this study to assess the feasibility and safety of a Simultaneous Integrated Boost (SIB) dose-escalated protocol at 45 Gy, 50 Gy and 55 Gy in 5 consecutive daily fractions, in Border Line Resectable Pancreatic Cancer (BRCP) /Locally Advanced Pancreatic Cancer (LAPC) by means of a standard LINAC platform. Methods: Patients diagnosed of BRPC/LAPC, candidates for neoadjuvant chemotherapy and SBRT, in four university hospitals of the province of Las Palmas (Canary Islands, Spain) were included in this prospective study. Radiotherapy was administered using standard technology (LINACS) with advanced positioning (Lipiodol® and metallic stent used as fiducial markers) and tumor motion control (4D, DBH, Calypso®). There were 3 planned dose-escalated SIB groups, 45 Gy/5f (9 patients) 50 Gy/5f (9 + 9 patients) and 55 Gy/5f (9 patients). The defined primary end points of the study were the safety and feasibility of the proposed treatment protocol. Secondary endpoints included radiological tumor response after SBRT, local control and survival. Results: From June 2017 to December 2022, sixty-two patients were initially assessed for eligibility in the study in the four participating centers, and 49 were candidates for chemotherapy (CHT). Forty-one were referred to radiotherapy after CHT and 33 finally were treated by escalated-dose SIB, 45 Gy (9 patients) 50 Gy (16 patients), 55 Gy(8 patients). All patients completed the scheduled treatment and no acute or late severe (≥grade3) gastrointestinal toxicity was observed.Local response was analyzed by CT/MRI two months after the end of SBRT. Ten patients (31,25 %) achieved objective response (2/9:45 Gy, 5/15:50 Gy, 3/8:55 Gy). Follow-up was closed as July 2023. Freedom from local progression at 1-2y were 89,3% (95 %CI:83,4-95,2%) and 66 % (95 %CI:54,6-77,4%) respectively. The 1-2y survival rates were 95,7% (95 %CI:91,4-100 % and 48,6% (95 %CI:37,7-59,5%) respectively. Conclusion: These promising results should be confirmed by further studies with larger sample size and extended follow-up period.

8.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335333

RESUMO

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

9.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(5): 209-212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38401598

RESUMO

Ocular neuromyotonia (ONM) is an infrequent disorder characterised by recurrent episodes of binocular diplopia caused by paroxysmal contraction of one or several extraocular muscles innervated by the same cranial nerve. It can be triggered spontaneously or caused by prolonged contraction of specific eye muscle(s) and is usually related to a local intracranial radiotherapy antecedent. We report the case of a 46-year-old woman who developed intermittent episodes of binocular diplopia eight years after radiotherapy for a nasopharyngeal carcinoma. After a complete neuro-ophthalmic assessment we diagnosed the case as an abducens nerve neuromyotonia. Although it is infrequent, radiotherapy to the nasopharynx is a possible cause of ONM, due to the proximity to the base of the skull and extraocular motor nerve pathways, especially that of the VI cranial nerve, as is the case presented in this article, about a patient whose history is a nasopharyngeal carcinoma treated with local radiotherapy.


Assuntos
Diplopia , Síndrome de Isaacs , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/radioterapia , Síndrome de Isaacs/etiologia , Síndrome de Isaacs/diagnóstico , Carcinoma Nasofaríngeo/radioterapia , Diplopia/etiologia , Carcinoma/radioterapia , Doenças do Nervo Abducente/etiologia , Lesões por Radiação/etiologia , Lesões por Radiação/complicações , Radioterapia/efeitos adversos
10.
Actas Dermosifiliogr ; 2024 Feb 19.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38382752

RESUMO

BACKGROUND AND OBJECTIVE: Burnout syndrome is a mental health disorder due to chronic occupational stress. Both burnout and associated comorbidities are prevalent among health care professionals, being medical residents a vulnerable group. Despite this, the scientific medical literature currently available on this issue in dermatology residents is scarce. The aim of this study was to analyze the prevalence of the burnout syndrome, anxiety, and depression in dermatology residents, and the associated risk factors. METHODS: This was a cross-sectional trial designed to include dermatology residents from Spain from December 2022 through June 2023. A self-administered form was sent via online messaging applications, including validated scales to study professional quality of life, burnout syndrome, anxiety, and depression. RESULTS: A total of 48 dermatology residents were included in the study, 50% of whom (24/48) were women, with a mean age of 27 years (1.25). A total of 58.33% (28/48) of the residents had some degree of anxiety, 22.9% (11/48) some degree of depression, and 23.4% a moderate risk of burnout (11/48). Workload was the main risk factor associated with the 3 disorders studied, while managerial support or intrinsic motivation seem to play a protective role. CONCLUSIONS: Burnout syndrome and its comorbidities are both prevalent in dermatology residents in Spain and closely related to each other.

11.
J Chem Phys ; 160(7)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38364009

RESUMO

Bromine atom (Br) reactions lead to ozone depletion in the troposphere and stratosphere. Photodegradation of bromocarbons is one of the main sources of bromine atoms in the atmosphere. Here, we use high-level ab initio methods, including spin-orbit effects, to study the photodissociation of the CH2Br radical. All possible fragmentation pathways, namely CH2Br + hν → CH2 + Br, HCBr + H, and CBr + H2, have been analyzed. Potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distance of each pathway have been calculated. Considering the actinic fluxes of solar irradiation in the troposphere and in the stratosphere in the relevant range of frequencies, it is found that the first five excited states of CH2Br can be accessed from the ground state. Analysis of the potential curves shows that the pathways producing CH2 + Br and HCBr + H can proceed through a fast direct dissociation mechanism, while the pathway leading to CBr + H2 involves much slower dissociation mechanisms like internal conversion between electronic states, predissociation, or tunneling through exit barriers. The main implications are that the two faster channels are predicted to be dominant, and the slower pathway is expected to be less relevant. The tropospheric and stratospheric solar actinic fluxes also allow for further dissociation of the HCBr and CBr fragments, generating additional Br atoms, provided that they survive possible collisions with other atmospheric reagents. Finally, we discuss the possible effect of each of the three CH2Br dissociation pathways on the depletion of atmospheric ozone.

13.
Rev Esp Quimioter ; 37(2): 149-157, 2024 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-38240196

RESUMO

OBJECTIVE: To compare quality of life, in patients living with HIV infection with pharmaceutical care according to the CMO methodology: capacity, motivation and opportunity versus conventional follow-up. METHODS: Longitudinal, prospective, multicenter, health intervention study, conducted between October 2019 and November 2021 in 14 centers throughout Spain. Patients over 18 years of age, receiving antiretroviral treatment and attending the consultations of the participating Pharmacy Services for 1 year were included. Patients who did not have the autonomy to complete the planned questionnaires were excluded. At baseline, participating centers were randomized to continue using the same systematics of work (traditional follow-up) or to implement the CMO model using patient stratification models, goal setting in relation to pharmacotherapy, use of motivational interviewing, as well as longitudinal follow-up enabled by new technologies. The main variable was the difference in the number of dimensions positively affected in each follow-up arm at 24 weeks of follow-up according to the MOS-HIV questionnaire. In the CMO group, the interventions performed the most frequently were recorded. RESULTS: 151 patients were included. The median age was 51.35 years. A significant improvement in quality of life was found at the end of follow-up in the CMO group, reducing the number of patients with negatively affected dimensions (2/11 vs 8/11). The most frequent interventions carried out in the CMO group, according to the taxonomy, were Motivation (51,7%) and review and validation (49,4%). CONCLUSIONS: The quality of life of patients is higher in those centers that develop Pharmaceutical Care based on the CMO methodology compared to traditional follow-up.


Assuntos
Infecções por HIV , Assistência Farmacêutica , Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Infecções por HIV/tratamento farmacológico , Seguimentos , Qualidade de Vida , Estudos Prospectivos
14.
Actas Dermosifiliogr ; 115(3): T224-T230, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38185206

RESUMO

BACKGROUND: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. OBJECTIVE: To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. MATERIAL & METHODS: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. RESULTS: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. CONCLUSIONS: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.


Assuntos
COVID-19 , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Pandemias , COVID-19/epidemiologia , Estudos Transversais
15.
Actas Dermosifiliogr ; 115(3): T231-T236, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38242430

RESUMO

BACKGROUND AND OBJECTIVE: Quality of professional life (QPL) is defined as a sense of well-being derived from a balance between the challenges of work and the resources available to deal with them. Impaired QPL can contribute to burnout. The aim of this study was to evaluate QPL in Spanish dermatologists using a validated questionnaire. MATERIAL AND METHODS: We designed a cross-sectional study in which Spanish dermatologists were invited to complete an online questionnaire sent out by messaging applications. The dermatologists were asked to provide sociodemographic information, answer 3 open questions, and complete the 35-item Spanish QPL questionnaire (Spanish abbreviation, CVP-35). RESULTS: We analyzed the information submitted by 106 dermatologists (62 women, 58%) with a mean age of 41 years (95% CI, 43.3-38.8 years). Women and department heads scored significantly higher in the workload domain of the questionnaire (P=.02 and P=.005, respectively). A heavy caseload was mentioned as the main factor contributing to impaired QPL and the main change in the wake of the COVID-19 pandemic. CONCLUSIONS: Female dermatologists reported heavier workloads. Heavy caseloads and more remote work were the main changes identified after the COVID-19 pandemic. Heavy caseloads have a significant impact on the QPL of dermatologists in Spain. Reducing caseloads would improve general job satisfaction and quality of care provision.


Assuntos
Esgotamento Profissional , COVID-19 , Humanos , Feminino , Adulto , Dermatologistas , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Satisfação no Emprego , Inquéritos e Questionários , Esgotamento Profissional/epidemiologia
16.
Sci Total Environ ; 913: 169677, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38163594

RESUMO

Microplastics (MPs) and antifouling paint particles (APPs) are important components of marine microdebris (MDs), which constitute a potential environmental risk. This study analyzed baseline contamination levels of MDs and mesodebris (MesDs) in intertidal sediments at different depths, exploring the geomorphological influence in three Argentine coastal environments: Bahía Blanca Estuary (BBE), Los Pocitos (LP) and Puerto Madryn (PM). The MDs and MesDs samples were characterized by µ-FTIR, SEM/EDX and XRD. The abundance of MPs and APPs in sediments, range between 19.78 and 1087.19 and between 0 and 172.93 items/kg d.w., respectively. Despite variations in population and industrial developments in these areas, MPs abundance shows no significant differences in low and high intertidal zones. However, mean MPs concentrations were higher in the surface layer (0-5 cm) compared to the deeper sediments (5-10 cm), indicating recent MPs deposition. Chemical characterization evidenced the presence of cellulose (CE) and denser polymers as acrylonitrile butadiene styrene (ABS) and polyacrylics (PAN), APPs, metallic and black MDs. Surface degradation and heavy metals (Zn, Cr, and Ba) were also detected in APPs and other MDs, either as additives or adhered to their surfaces. Changes in crystallinity were also observed on the MesDs due to weathering. The calculated polymer hazard index (PHI) and the presence of hazardous polymers such as ABS and PAN indicated an increased risk of MPs pollution on the BBE and PM coasts. The pollution load index (PLI) values (from 4.63 to 5.34) suggested unpolluted to moderately polluted levels. These findings offer insights into potential risks associated with MDs in Argentine intertidal sediments, underscoring the critical need to comprehend the geomorphology and the influence of coastal dynamics. This is crucial for effectively addressing challenges linked to MDs pollution guiding the development of robust management and mitigation strategies.

17.
Sci Total Environ ; 914: 170026, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218486

RESUMO

Estuarine coastal water and sediments collected from multiple locations within the middle Río de la Plata (RDLP) estuary were analyzed in order to identify the presence of microplastics (MPs, <5 mm) and mesoplastics (MePs, 5-25 mm) in one of the most significant estuaries in the Southwestern Atlantic. The present study represents one of the first researches to survey MPs and MePs contamination in key stations at RDLP estuary. Average concentrations of 14.17 ± 5.50 MPs/L and 10.00 MePs/L were detected in water samples, while 547.83 ± 620.06 MPs/kg (dry weight) and 74.23 ± 47.29 MePs/kg d.w. were recorded in sediments. The greatest abundances were observed in the more anthropized areas, near urban settlements. Fibers were the most conspicuous plastic items in water and sediments, followed by fragments. On the other hand, surface sediments, and 50 cm and 100 cm-depth sediments also presented MPs and MePs indicating they could serve as a stratigraphic indicator for recently formed sediments. The main polymer type identified were acrylic fibers, followed by polypropylene (PP) and polyethylene terephthalate (PET). Besides, SEM-EDX detected the presence of Si, Fe, Ti, Al and Cl onto the plastics' surface. These elements may serve as additives to enhance the plastics' properties, such as in the case of Ti, or they could originate from the environment, like biogenic Si or Fe, and Al possibly as a component of the suspended particles or sediments adhered to the micro or meso plastics. Finally, the results of the present study showed that MPs and MePs are commonly found in waters and also tend to be trapped in sediments of the RDLP estuary supporting the assertion that these areas play a substantial role in influencing the transport, dispersion, and buildup of MPs in estuarine regions.

19.
Food Chem ; 442: 138421, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244443

RESUMO

A systematic kinetic study was conducted in subcritical water medium in the temperature range from 150 to 200 °C for pure glucose, xylose, proline and aspartic acid as well as binary mixtures of sugars + amino acids to understand the reaction kinetics and interactions among biomass components and to discern the influence of Maillard reaction (MR) on the overall reaction kinetics. The main degradation products identified for glucose and xylose were the respective dehydration products, hydroxymethyl furfural and furfural, yielding an increasing solid residue with temperature (15.9 wt% at 200 °C) with an augmented heating value. The degradation of sugars and amino acids in binary systems was faster compared to pure compounds due to MR and the production of dehydration products was delayed when considering total sugar conversion. Higher relative reactivity in MR was observed for xylose over glucose showing also higher antioxidant activity.


Assuntos
Aminoácidos , Xilose , Humanos , Xilose/química , Glucose/química , Açúcares , Ácido Aspártico/química , Prolina , Água/química , Furaldeído/química , Reação de Maillard , Desidratação , Cinética
20.
J Dairy Sci ; 107(5): 3280-3291, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37977445

RESUMO

The preweaning period for a dairy calf is characterized by high morbidity and mortality rates, leading to financial losses for producers. Identifying strategies to improve the health and welfare of calves while reducing antimicrobial use continues to be crucial to the success of the dairy industry. The objective of this study was to determine the effects of feeding colostrum replacer (CR) to dairy heifer calves beyond d 1 of life on growth, serum IgG, the incidence of diarrhea and bovine respiratory disease (BRD), and the risk of mortality in the preweaning period. At birth, Holstein heifer calves (n = 200; 50/treatment) weighing 40.7 ± 0.35 kg (mean ± SE) were fed 3.2 L of CR (205 g IgG/feeding) at 0 h and 12 h of life. Calves were then randomly assigned to 1 of 4 treatments: 450 g of milk replacer (MR) from d 2 to 14 (control, CON), 380 g of CR + 225 g of MR from d 2 to 3, then 450 g of MR from d 4 to 14 (transition, TRAN), 45 g of CR + 450 g of MR from d 2 to 14 (extended, EXT); or 380 g of CR + 225 g of MR from d 2 to 3, then 45 g of CR + 450 g of MR from d 4 to 14 (transition + extended, TRAN+EXT). Each treatment was reconstituted to 3 L and fed twice daily. All CR treatments were fed using bovine-derived CR containing 27% IgG. From d 15 to 41, all calves were fed 600 g of MR reconstituted to 4 L twice daily. Body weight was recorded at birth and every 7 d until study completion on d 49. Blood samples were taken daily until d 7 to evaluate serum IgG and then every 7 d until d 49. A health assessment was performed daily to evaluate calves for BRD and diarrhea. Data were analyzed using mixed linear regression, mixed logistic regression, and survival analysis models in SAS 9.4. Serum IgG concentrations were not affected by treatment for the study period. The EXT and TRAN+EXT groups had greater average daily gain (ADG) from d 7 to 14 (0.14 kg/d) and the TRAN group had greater ADG from d 14 to 21 (0.11 kg/d), compared with CON. There was no association of treatment with the odds or the duration of a diarrhea bout. However, provision of CR to the TRAN and EXT calves was associated with a reduced hazard of diarrhea compared with CON calves. Furthermore, TRAN and EXT calves have a lower hazard of mortality compared with CON calves, with TRAN and EXT calves had a 2.8- and 3.8-times lower hazard of mortality, respectively. Our findings suggest that the supplementation of CR to dairy calves positively affects ADG, and reduces the hazard of diarrhea and mortality during the preweaning period. Future research should look to further refine the supplementation strategy of CR to calves and explore the mechanism of action.

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